delt_T=0.001;
A=zeros(1,5000);
T=1;
y0=0;
yk_1=y0;
u=0;
for i=1:1:5000
    if(i==1000)
        u=1;
    end
    yk=(yk_1+delt_T/T*u)/(1+delt_T/T);
    yk_1=yk;
    A(i)=yk;
end
t=0:0.001:4.999;
hold on;
plot(t,A)

